Moisture quasi-equilibrium theory postulates that the instability index, a measure of low to mid-tropospheric moist convective instability, is inversely proportional to saturation fraction, a good proxy for precipitation. We looked at thermodynamic properties for 16 convective events from dropsonde data collected during the field project Organization of Tropical East Pacific Convection (OTREC). OTREC2019 performed 22 flights in the Eastern Pacific and Southwest Caribbean out of Costa Rica using the NSF/NCAR Gulfstream V aircraft. Convective available potential energy and saturation fraction show weak anti-correlation, while the instability index and saturation fraction are more strongly anti-correlated. This supports the moisture quasi-equilibrium hypothesis. Vertical mass flux profiles are calculated for all 16 convective events (8 convective cases in the tropical Eastern Pacific, 5 off the Pacific coast of Colombia and 3 in the Southwest Caribbean). Every developing convective case has a bottom-heavy vertical mass flux profile and every decaying case has top-heavy profile.